1 #include "str.h"

     2 

     3 int str_diffn(s,t,len)

     4 register char *s;

     5 register char *t;

     6 unsigned int len;

     7 {

     8   register char x;

     9 

    10   for (;;) {

    11     if (!len--) return 0; x = *s; if (x != *t) break; if (!x) break; ++s; ++t;

    12     if (!len--) return 0; x = *s; if (x != *t) break; if (!x) break; ++s; ++t;

    13     if (!len--) return 0; x = *s; if (x != *t) break; if (!x) break; ++s; ++t;

    14     if (!len--) return 0; x = *s; if (x != *t) break; if (!x) break; ++s; ++t;

    15   }

    16   return ((int)(unsigned int)(unsigned char) x)

    17        - ((int)(unsigned int)(unsigned char) *t);

    18 }